Alternate Text for Images

The basic idea of alternate text is a clear description of what an image is, so when a screen reader sees an image, it can read the alt text and convey to the user what exactly the image is, in content and functionality.

Images need to be described so the user of the website knows what they are. Images that are just "filler" do not need alt text, they can just have "alt = "", which means "null".

With regards to tables that may be present, atl text is not needed, because the title of the table should explain the content of the table.